tsac-ng — Neural Audio Codec (Multi-Backend)

tsac-ng v0.1.0 — Clean-room implementation of a neural audio codec, independently developed from first principles. Compatible with the .txc container format and .bin model files used by TSAC.

Relationship to TSAC: Like Linux to Unix — same ecosystem compatibility, built from scratch with zero shared code.

Features

• 5 CPU SIMD levels across 3 architectures (x86-64 AVX/AVX2/AVX-512, ARM NEON/SVE, RISC-V RVV)
• 3 GPU backends: CUDA (NVIDIA), HIP/ROCm (AMD), Vulkan (cross-platform)
• 1 experimental backend: LLVM JIT
• Runtime CPUID dispatch — auto-selects best SIMD with scalar fallback
• Zero system() calls — fully self-contained
• CLI compatible with original tsac (2024-04-08)

Quick Start

# Build (CPU backend, x86-64)
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
make -j$(nproc)

# Decompress
./tsac-ng -v d input.txc output.wav

# With CUDA
cmake .. -DUSE_CUDA=ON -DCUDAToolkit_ROOT=/opt/cuda
./tsac-ng --cuda -v d input.txc output.wav

# With HIP/ROCm
cmake .. -DUSE_HIP=ON -DHIP_PATH=/opt/rocm
./tsac-ng --hip -v d input.txc output.wav

Backend Status

Backend	Build	Runtime	Notes
CPU (x86-64)	✅	✅	AVX/AVX2/AVX-512 auto-dispatch
CPU (ARM64)	✅	✅	NEON + SVE auto-detect
CPU (RISC-V)	✅	✅	RVV + scalar fallback
CUDA	✅	✅	SM 8.0+, Runtime API
HIP/ROCm	✅	✅	gfx1030+, ROCm 7.x
Vulkan	✅	⚠️	Cross-compile for ARM64 Mali
LLVM JIT	✅	⚠️	Experimental, init hangs on LLVM 22

Architecture

┌─────────────┐    ┌──────────────┐    ┌──────────────┐
│  .txc file  │───▶│  txc_format  │───▶│ codebook_idx │
└─────────────┘    └──────────────┘    └──────┬───────┘
                                              │
                    ┌─────────────────────────┘
                    ▼
┌──────────┐  RVQ lookup  ┌──────────┐  decode graph  ┌──────┐
│ .bin     │─────────────▶│  1024-d  │───────────────▶│ PCM  │
│ model    │  12 codebooks│ features  │  7-layer DAC  │audio │
└──────────┘              └──────────┘                └──────┘

Decoder graph: RVQ Codebook → Conv1d(1024→1536) → 4× ResidualBlock (1536→768→384→192→96) → Snake → Conv1d(96→2) → PCM

CLI Reference

tsac-ng [options] c|d|t infile outfile

Options (compatible with original tsac):
  --cuda, --hip, --vulkan, --llvm   GPU/accelerator backend
  -q, --n_codebooks n    Codebooks (1-12 stereo, 1-9 mono, default=max)
  -T n                   Thread count (default=1)
  -v                     Verbose mode
  -h, --help             Show help
  -s, --separate_channels  Stereo as dual mono
  -c, --channels n       Force channel count
  -f, --fast             Fast mode (no transformer)
  -m, --model path       Model file path
  -M, --trf_model path   Transformer model path
  --batch_size n         Batch size (default=auto)

Cross-Compilation

# ARM64 (Termux, Raspberry Pi 5, etc.)
cmake .. -DCMAKE_TOOLCHAIN_FILE=cmake/Toolchain-arm64.cmake

# RISC-V (experimental)
cmake .. -DCMAKE_TOOLCHAIN_FILE=cmake/Toolchain-riscv64.cmake

Project Structure

tsac-ng/
├── src/
│   ├── cpu_decoder.c      # CPU decoder + x86 SIMD dispatch
│   ├── tsac_codec.c       # Codec API + WAV I/O
│   ├── txc_format.c       # .txc container parser
│   ├── model_loader.c     # .bin model loader (BF8/float32)
│   ├── main.c             # CLI (compatible with original tsac)
│   ├── cuda/              # CUDA backend
│   │   ├── cuda_kernels.cu
│   │   └── cuda_backend.cu
│   ├── llvm/              # LLVM JIT backend (experimental)
│   ├── vulkan/            # Vulkan compute backend
│   ├── arch/arm/          # ARM NEON + SVE
│   └── arch/riscv/        # RISC-V RVV
├── hip/                   # HIP/ROCm backend
├── include/               # Public headers
├── cmake/                 # Toolchain files
└── experimental/          # Experimental code

Compatibility

• .txc container format (original TSAC)
• .bin model files (DAC stereo/mono, q8)
• Original tsac CLI arguments

License

MIT

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tsac-ng v0.1.0 — Copyright (c) 2026 Hope2333 (幽零小喵)